Only a few dozen people worldwide have been officially documented as suffering from the syndrome since it was first recorded in 1907. It is linked to damage to the part of the brain that controls speech.

In 2010 a New Zealand woman with multiple sclerosis found her Kiwi tones turning into a mix of Welsh, Scottish and North London accents and a subsequent scan revealed two lesions on her brain.

Other known cases include an English woman speaking with a French accent after having a stroke and a Norwegian woman who spoke with an apparent German accent after being hit by shrapnel in 1941.

Three years ago a woman in England reportedly began speaking with a Chinese accent after suffering a migraine.